Variable from person-to-person based upon the quality of housing they choose to live in, not variable month-to-month. Should someone living in a luxury penthou

Variable from person-to-person based upon the quality of housing they choose to live in, not variable month-to-month. Should someone living in a luxury penthouse suite at 15K+ a month get to deduct his rent at 100%, as well as closet-sized studio apartment? If not, where is the line drawn? This is what I mean when I talk about value-based judgements based on variable rates. Should I be able to deduct only what is literally the cheapest rent in my city? What if the cheapest apartment is full, and there's no way I could possibly get that rate? Should it be the cheapest AVAILABLE rate? Would this then impact prices knowing that the lowest rate drives tax-deductibility for all citizens? This is the labyrinthine decision tree that opens up when deducting things like rent, food, clothing, etc. Also, if SALT deductions truly incentivized punitive state taxes, why are so many states still charging 0% tax rates?